This invention relates to a scanner, in particular to a function control key for the scanner.
In traditional design for a scanner, the control key is a mechanical switch, which triggers certain operation to start or produces a certain signal to trigger a pre-programmed function. To accomplish such a series of operations, a number of switching operations may be required for connection to a special motherboard with circuits for different functions. The multiple switches, the multiple wiring connections, and the extra mother board all increase the cost of the scanner.
Further more, electronic switches must carry current. Such current carrying switches may wear out in time.